Fuel Pump

The fuel pump used in this system is a positive displacement, roller vane immersible pump with a permanent magnet electric motor. The fuel is drawn in through a filter sock and pushed through the electric motor to the outlet. The pump contains two check valves. One valve is used to relieve internal fuel pump pressure and regulate maximum pump output. The other check valve, located near the pump outlet, restricts fuel movement in either direction when the pump is not operational. Voltage to operate the pump is supplied through the Auto Shut Down (ASD) relay.

Fig. Fig. 1: TBI style fuel pump

TESTING

Refer to the preceding Fuel System Pressure testing procedure.

REMOVAL & INSTALLATION

See Figures 2, 3, 4, 5, 6, 7 and 8

CAUTION

Observe all applicable safety precautions when working around fuel. Whenever servicing the fuel system, always work in a well ventilated area. Do not allow fuel spray or vapors to come in contact with a spark or open flame. Keep a dry chemical fire extinguisher near the work area. Always keep fuel in a container specifically designed for fuel storage; also, always properly seal fuel containers to avoid the possibility of fire or explosion.

Properly relieve the fuel system pressure.

Disconnect the negative battery cable.

Raise and support vehicle.

Remove the fuel tank from the vehicle.

Remove the holding clamp and lift out the fuel pump module.

Remove the sending unit attaching screws from the mounting bracket located on the drain tube.

Disconnect the wires from the sending unit and remove the sending unit.

Remove the drain tube from the mounting lug at the bottom of the reservoir.

Remove the lowermost coil of the drain tube from the mounting lugs on top of the reservoir. Be careful to avoid unsnapping the return line check valve cover from the bottom of the reservoir.

Release the pump mounting bracket from the reservoir. Press the bracket with both thumbs toward the center of the reservoir.

Remove the pump mounting bracket and rubber collar from the hose. Cut the hose clamp on the supply line and discard the clamp. Remove the pump/filter assembly. Pry the filter from the pump.

To install:

Press a new filter onto the pump.

Using a new clamp, attach the supply hose.

Position the pump mounting bracket and rubber collar on the supply hose between the bulge in the hose and the pump.

Position the pump in the reservoir so that the filter aligns with the cavity in the reservoir.

Snap the pump bracket into the reservoir.

Position the coil tube on the reservoir so that the drain tube aligns with the mounting lugs on the reservoir.

Snap the lower-most coil into the mounting lugs on top of the reservoir.

Snap the drain tube into the lugs on the bottom of the reservoir.

Connect the wires to the new sending unit.

Align the index tab on the level unit with the index hole in the mounting bracket.

Install the level unit screws.

Install the assembly in the tank.

Lower the vehicle.

Connect the negative battery cable.

Fig. Fig. 2: Note the various components on top of a TBI style fuel pump assembly

Fig. Fig. 3: Remove the retaining clamp from a TBI style fuel pump

Fig. Fig. 4: Remove the fuel line coil from the reservoir

Fig. Fig. 5: Note the location of the fuel gauge sending unit

Fig. Fig. 6: Mark them for identification, then detach the wires from the terminals on the sending unit